Or "over nutrition" which entails a lot of extra calories and leads to obesity....add DNA and other factors and one just can't win (unless in the group that seems to be able to shrug anything off).
There are those that believe that many of those who are obese are also suffering from poor nutrition. If you need x-units of a particular vitamin, but your food choices are deficient of that particular vitamin, your body will still seek out that vitamin and cause you to overeat to acquire what you need.